VARIATION. 175 



and have several times had individuals that tried to go over into a 

 second year, this is the first time that one has done so successfully. 

 Such cases have been recorded, but the occurrence is a rare one, as is 

 shown by its having only now presented itself in ray experience after 

 long-continued breeding of the species. In this particular, C. })si and 

 C. tridens contrast markedly with C. leporina, wliich rather prefers to go 

 over into a second j^ear, and often takes a third or a fourth year in jDupa. 



3. A number of eggs of Pachetra leucophaea were sent to me 



from Kent last spring by my friend, Mr. Jeffreys, and in the summer 

 I had twenty-four larvcB, of Avhich I sent away sixteen and kept eight. 

 These I treated in the same manner as those which I had in the year 

 1891, but for various reasons they did not receive so much attention 

 as those ; as a consequence, instead of obtaining three moths from five 

 larvaj, or the equally good results achieved in the following year by 

 Mrs. Hutchinson, I only succeeded in rearing one moth, which is now 

 in the collection of my friend, Mr. E. R. Bankes. So far as I can learn, 

 however, this is the only motli that has been bred from an unusual 

 number of eggs distributed last spring. — T. A. Chai'MAN, Firbank, 

 Hereford. June, 1894. 



WARIATION. 



Advancing backward : A note on melanism in manufacturing 

 DISTRICTS. — A marvellous case of advancing backwards occurs in a 

 paragraph written in an unsigned criticism in The British Nuturalist, 

 p. 152. It reads: — "With regard to the alleged increase of darker 

 insects in our manufacturing districts, we take leave to doubt the fact. 

 When the fact has been demonstrated we shall accept the theory 

 without hesitation ; we feel that it ought to be so, but think it is not." 

 Either the critic is entirely ignorant of Entomology, or he has studied 

 the subject such a short time that he has not yet informed himself of 



what is known about it, or But we must forbear ! The British 



Naturalist is published at Warrington. Some seventeen years ago 

 Mr. N. Cooke wrote: — "The most interesting case of melanism that 

 has come under my observation — and my friend, Mr. Greening of 

 Warrington, can say if I exaggerate the facts — is the total change in 

 the colour of Tephrosia hiundularia in Delamere Forest. Some thirty 

 years since, when he and 1 visited Petty Pool Wood, this species was 

 very abundant, but all were of a creamy-white ground colour ; dark 

 varieties were so scarce that they were considered a great prize. Now 

 it is the reverse, all are dark smoky-brown — approaching black ; a light 

 variety is very rare. The same change, and nearly to the same extent 

 as regards numbers, has come over Ainphidasys hettdaria. Throughout 

 the district from Petty Pool, including Warrington, to Manchester, the 

 black form is now usually found. I am inclined to suspect that climate 

 and manufactures have done more to bring about tliis change than 

 anything else. During the past thirty years what large towns have 

 sprung up to the west of this district ! Runcorn, Widnes, St. Helen's, 

 Earlstown, Wigan, etc., all pouring forth from their tall chimneys 

 chemical fumes and coal smoke, which emanations are carried over our 

 collecting grounds by every westerly wind." A number of similar 



